Dual differential stacking

ABSTRACT

Stacking empty trays, sensing occupancy of each tray seriatim, interdicting the stacking of any tray found to contain matter, e.g. eggs and egg whites, etc., moving such tray to a different position, and stacking such trays at this position, including automatic mechanisms for this purpose.

United States Patent Inventor William H. Warren West Brookfield, Mass. (East Brookfield Road North Brookfield, Mass. 01535) Appl. No. 811,684 Filed Mar. 3, 1969 Patented Apr. 27, 1971 DUAL DIFFERENTIAL STACKING 8 Claims, 2 Drawing Figs.

US. Cl 209/74 Int. Cl B07c 5/38 Field of Search 209/73, 74, 75; 53/(Inquired) [5 6] References Cited UNITED STATES PATENTS 3,450,258 6/1969 Poupin 209/74 3,461,716 8/1969 Thomson.... 209/74X 3,481,465 12/1969 Way 209/74 Primary Examiner-Allen N. Knowles Attorney-Charles R. Fay

ABSTRACT: Stacking empty trays, sensing occupancy of each tray seriatim, interdicting the stacking of any tray found to contain matter, e.g. eggs and egg whites, etc., moving such tray to a different position, and stacking such trays at this position, including automatic mechanisms for this purpose.

Pmmninmmn 3576;255

INVENTOR WILLIAM H. WARREN ATTORNEY DUAL DIFFERENTIAL STACKING BACKGROU ND OF THE INVENTION It is necessary to sense for and difierentiate empty trays issuing from e.g. an egg processing machine because eggs become stuck or break at times and the trays must be separated prior to further use. Stacking wet trays destroys the value of the tray above. This has been done in the prior art by stacking clean trays and allowing the others to pass by, to fall onto the floor or into a container. This results in the possible loss of good eggs, and the trays must be rehandled, requiring extra labor; the dumping of the trays usually breaks any good eggs making a mess, and extra machine space is needed. The present invention solves this problem by the stacking of good" clean trays in a column and also stacking the bad occupied or dirty (wet) trays in a separate column, avoiding any dumping of the bad trays.

SUMMARY OF THE INVENTION This is done by using electromechanical devices of known I sensing probes which are arranged in a row across a conveyor carrying the empty trays and sensing an undesired object as well as a wet egg cavity in the tray.

Just behind the electromechanical devices there are a pair of tandem stackers, the first of which stacks the good trays if no signal is received, but this stacker is interdicted in its action if a signal is received. When this happens, the tray necessarily proceedsto the second stacker which operates at all times. A holding circuit is provided to hold the first stacker out of operation until the bad tray has passed the first stacker.

Preferably the stacking is vertical and upwards so that stacks of good trays are easily removed and any bad tray is clearly visible in the second stack. Thus any bad tray is easily seen and removed and any good eggs retrieved, the tray then being either discarded or cleaned and returned to use. These is little loss of motion and the machine is kept clean and is more compact.

' BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a view in side elevation of a machine according to i the invention, parts being broken away, and

FIG. 2 is a plan view of the cam and camshaft operating the first stacker for good trays.

PREFERRED EMBODIMENT OF THE INVENTION moisture. In either case, a switch is activated, actuating a solenoid 16.

Each stacker has a horizontal table I8, 20, or the like, reciprocated vertically by separate lifter bars 22, 24. B, lifter bar has a fixed pivot support as at 26, 28 and a cam follower 30,32. There are a pair of cam shafts 34, 36, and shaft 34 has fixed to it a cam B which always runs. However, a cam A is detachably connected (clutched) with respect to its drive shaft 36 and is declutched and thus rendered inoperative upon the activation of the electromechanical sensing devices. Thus the stacker 18 at station A does not operate and the conveyor 12 carries the respective tray to station B. The B cam always operates in its timed sequence whether there is a tray present or not.

The clean trays stack evenly as illustrated but where a tray has an egg in it, as at station B, the stacking will be uneven. In any event, the operator has plenty of time to manually remove at his convenience the bad trays for cleaning and egg retrieval.

The solenoid 16 may operate a lever 38 to move a clutch part 40 parallel to shaft 36 to accomplish the clutching and declutching, and a hold circuit is provided, e.g. through the use of a roller microswitch on the cam face to hold the cam disengaged (after the impulse has passed) completely through the cycle, see switch 42. This circuit is not shown in detail and will be clear to anyone skilled in the art. This is a self-clearing circuit which allows the cam to return to original position as by a properly positioned low spot on the face of cam A.

lclaim:

I. In combination, a conveyor for trays which are largely empty and clean, electromechanical devices for determining whether any tray is actually occupied or soiled (wet),

a first means for stacking clean trays one at a time, in timed relation to the movement of the trays on the conveyor, means to hold temporarily the action of said first stacking means upon the sensing of a soiled (wet) or occupied tray, so that the latter fails to be stacked, the conveyor continuing the motion of said occupied or soiled (wet) tray,

and a second stacking means removing the occupied or soiled (wet) tray from the conveyor and stacking sub- 1 sequent occupied or soiled (wet) trays therewith.

2. The combination of claim 1 wherein the second stacking means operates continuously.

3. The combination of claim I wherein the stacking means elevate the trays to stack them.

4. The combination of claim 1 wherein the stacking means each include a vertically reciprocable table.

5. The combination of claim I wherein the stacking means each includes a vertically reciprocable member, and including a rotary-driven cam for each member whereby they are raised and lowered.

6. The combination of claim 1 wherein the stacking means each includes a vertically reciprocable member and a rotarydriven cam for ealch member whereby the members are raised and lowered and the means to halt the action of the first stacking means includes a clutch.

7. The combination of claim 1 wherein the stacking means each includes a vertically reciprocable member and a rotarydriven cam for each member whereby the members are raised and lowered and the means to halt the action of the first stacking means includes a clutch operated by means of a solenoid under signal from any of the electromechanical devices.

8. The combination of claim 1 wherein the second stacking means operates continuously. 

1. In combination, a conveyor for trays which are largely empty and clean, electromechanical devices for determining whether any tray is actually occupied or soiled (wet), a first means for stacking clean trays one at a time, in timed relation to the movement of the trays on the conveyor, means to hold temporarily the action of said first stacking means upon the sensing of a soiled (wet) or occupied tray, so that the latter fails to be stacked, the conveyor continuing the motion of said occupied or soiled (wet) tray, and a second stacking means removing the occupied or soiled (wet) tray from the conveyor and stacking subsequent occupied or soiled (wet) trays therewith.
 2. The combination of claim 1 wherein the second stacking means operates continuously.
 3. The combination of claim 1 wherein the stacking means elevate the trays to stack them.
 4. The combination of claim 1 wherein the stacking means each include a vertically reciprocable table.
 5. The combination of claim 1 wherein the stacking means each includes a vertically reciprocable member, and including a rotary-driven cam for each member whereby they are raised and lowered.
 6. The combination of claim 1 wherein the stacking means each includes a vertically reciprocable member and a rotary-driven cam for each member whereby the members are raised and lowered and the means to halt the action of the first stacking means includes a clutch.
 7. The combination of claim 1 wherein the stacking means each includes a vertically reciprocable member and a rotary-driven cam for each member whereby the members are raised and lowered and the means to halt the action of the first stacking means includes a clutch operated by means of a solenoid under signal from any of the electromechanical devices.
 8. The combination of claim 1 wherein the second stacking means operates continuously. 